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arXiv · 0810.2241

The global covariance matrix of tracks fitted with a Kalman filter and an application in detector alignment

Wouter Hulsbergen
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Abstract

We present an expression for the covariance matrix for the set of state vectors describing a track fitted with a Kalman filter. We demonstrate that this expression facilitates the use of a Kalman filter track model in a minimum $χ^2$ algorithm for the alignment of tracking detectors. We also show that it allows to incorporate vertex constraints in such a procedure without refitting the tracks.

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Wouter Hulsbergen. 2008-11-18. The global covariance matrix of tracks fitted with a Kalman filter and an application in detector alignment. https://doi.org/10.1016/j.nima.2008.11.094

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